In rectangle ABCD. Ac = 3x + 15 and Bd = 4x - 5 find the length of ac

Question

I need help on how to solve this problem and finding the correct answer 

Answer 1

The rectangle has sides AB, BC, CD, and AD.  Then AC and BD are diagonals of the rectangle.  The diagonals have the same length.

 

AC = BD

 

3x + 15 = 4x - 5

 

 

Solve the equation for x.

 

x = 20

 

 

Plug this value of x back into any of the expressions.